This invention relates to carotenoid pigments extractable from natural sources.
There is a need for a cost-effective natural source of astaxanthin, which is the carotenoid pigment that contributes the characteristic pink or red colour to the flesh of wild salmon. Salmonid fish are extensively farmed today, and there is a commercial need to produce such fish possessing a nature-identical flesh colour.
Astaxanthin occurs in various marine animals, such as crustacea, but its extraction from such sources is uneconomic. It is also possible to synthesise astaxanthin, but this is expensive, and moreover the use of such synthetic pigment does not convey the connotation of `natural` that many consumers regard as desirable.
Astaxanthin occurs in certain plants, especially certain species belonging to the genus Adonis. One such species is Adonis aestivalis, where it occurs predominantly in the petals of the bright red flowers. However, the reported wild strains of Adonis aestivalis possess only flower heads with very few petals, and the proportion of astaxanthin pigment relative to the total mass of the plant is too small for it to be cultivated and extracted on any sensible commercial scale.